I had the same problem but with a bit of trial and error i found the solution
firstly click on the control panel in the start button, now select add or remove programs, a new window will open. Now select Add/Remove Windows Components. A list will appear with all the components that your windows system can have installed with check boxes to the left. If the problem is the same as what i had, you should see that the Accessories and Utilities component has been deactivated, click on the check box and then click next to install the accessories and games again. By the way I use windows XP, but the method should be te same for older versions of windows
hope this helps.
